U.S. President Barack Obama held a town hall meeting Monday using an unusual venue - the YouTube Internet Web site. He took questions submitted via e-mail and video during and following his State of the Union address last week.

The president has engaged in live question and answer sessions on the White House Web site. But this is his first Internet town hall meeting on a privately owned and operated site.

Most of the questions dealt with domestic policy. But YouTube says there were also many queries dealing with national security.

President Obama answered three national security questions. His answers were posted live on YouTube and the White House link on Facebook, a popular social networking site.

He responded to a question about combating terrorism by stressing that the United States has to have a balanced policy that includes military, diplomatic and development components.

"We want to use all of our national power to deal with the problem of these extremist organizations," said President Obama. "But part of that does involve applications of military power."

Mr. Obama also discussed why it is taking longer than he expected to close the U.S. detention facility at Guantanamo Bay, Cuba. He said the situation is complex, noting that there is resistance to moving detainees to facilities in the United States.

"One of the things that we have had to try to communicate to the country at large is that historically, we have tried a lot of terrorists in our courts," said Mr. Obama. "We have them in our federal prisons; they have never escaped. And these folks are not different."

Not all of the questions were posed by individuals. A group called the Enough Project, which campaigns against genocide and crimes against humanity, submitted a video to YouTube, urging President Obama to do more to help the people of Sudan.

Mr. Obama said the situation there is heartbreaking and difficult. He said the United States is working with regional powers and the United Nations to broker a series of agreements that would stabilize the country.

"We continue to put pressure on the Sudanese government," said President Obama. "If they are not cooperative in these efforts, then it is going to be appropriate for us to conclude that engagement does not work. And we are going to have to apply additional pressure on Sudan in order to achieve our objectives."

But the president quickly added he remains hopeful that diplomacy will work and that agreements can be brokered with all of the parties involved.